基于Eulerian-Lagrangian模型的库区溶解气体时空分布和对鱼类影响的模拟  

Numerical predictions of the total dissolved air distribution and its effect on fish in a reservoir with the Eulerian-Lagrangian model

作　　者：黄菊萍[1] 黄膺翰 欧洋铭 王远铭[1] 冯镜洁[1] 李然[1] HUANG Juping;HUANG Yinghan;OU Yangming;WANG Yuanming;FENG Jingjie;LI Ran(State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China;Power China Zhongnan Engineering Corporation Limited,Changsha 410014,China;College of Architecture and Civil Engineering,Chengdu University,Chengdu 610106,China)

机构地区：[1]四川大学水力学与山区河流开发保护国家重点实验室,成都610065 [2]中国电建集团中南勘测设计研究院有限公司,长沙410014 [3]成都大学建筑与土木工程学院,成都610106

出　　处：《清华大学学报（自然科学版）》2021年第6期601-609,共9页Journal of Tsinghua University(Science and Technology)

基　　金：国家重点研发计划项目资助(2016YFC0401710);国家自然科学基金面上项目(51879173)。

摘　　要：大坝泄水会导致下游水体出现总溶解气体(total dissolved gas,TDG)过饱和。过饱和TDG可能导致鱼类患气泡病甚至死亡。受模拟方法的局限,Eulerian法和Lagrangian法均不能同时模拟TDG的分布和持续滞留时间,因而制约了对鱼类受过饱和TDG影响程度的定量判别。基于此,该文开发建立了鱼类受过饱和TDG影响的三维Eulerian-Lagrangian模型,其中Eulerian模型考虑了过饱和TDG在水体内部的释放与在自由表面的传质;Lagrangian模型在Eulerian模型基础上引入粒子追踪方法,模拟得到各个粒子在不同TDG饱和度下的滞留时间,即TDG持续滞留时间,并以TDG的持续滞留时间为参考因子以分析TDG对鱼类的影响。本研究以大渡河铜街子电站库区为例,开展了过饱和TDG输移释放及其滞留时间的数值模拟,并基于已有的典型鱼类对过饱和TDG耐受性实验成果,定量分析得到了过饱和TDG对鱼类的影响程度。为研究过饱和TDG对鱼类影响提供了一种方法和思路,为泄洪方案的优化研究提供了科学依据和技术支撑。Flow over a spillway discharge becomes supersaturated with dissolved air.The air slowly dissipatesbut the water remains supersaturated a long distance downstream of the dam,especially in the deep reservoir areas of cascade power stations.The supersaturated air can then be lethal to fish.Current research cannot completely simulate the fish movements and exposure timesin the various gas concentrations;therefore,the total dissolved gas(TDG)residence time was used to characterize the influence of the gas on fish in this study.However,neither the Eulerian model nor the Lagrangian model can simulate both the gas distribution and the residence time.Thus,this study used a combined three dimensional Eulerian-Lagrangian model of the air dissipation including dissipation in the water and mass transfer at the water surface.Particle tracking was used to estimate the tailrace residence time and the gas exposure time.The model was used to estimate the fish injury probability due to supersaturated air in the Tongjiezi reservoir in the Dadu River based on previous experimental data for the fish air tolerance ability.This study provides a method to analyze fish injury from supersaturated air and to optimize spillwaydischarge flows.

关 键 词：Eulerian-Lagrangian模型 总溶解气体 鱼类生境 OPENFOAM 

分 类 号：TV131.32[水利工程—水力学及河流动力学]